Method and apparatus to erect pile fibers

ABSTRACT

A method and apparatus to allow the pile of a pile fabric to become substantially erect by heating the pile fabric to a temperature between the heat setting and dyeing temperatures of the fabric and applying a vibratory force thereto. The vibratory force is applied by impinging a high velocity air stream against a flexible diaphragm over which the heated pile fabric is passed.

This invention relates to a method and apparatus to vibrate pilefabrics, particularly synthetic or partly synthetic fabrics, to removepile distortions created therein after heat setting and/or duringdyeing.

In the case of pile fabrics which have been heat set at a hightemperature with the pile erect and then dyed at a lower temperatureduring which the pile is substantially disturbed, as in jet dyeing, itis possible to return the pile to its original erect condition byheating the fabric to a temperature intermediate to that of heat settingand dyeing and simultaneously agitating the fabric, which typically mustcarry a large static charge for the process to be effective. Pile fabricprocessed in this way has a clearer, more uniform appearance than pilewhich has been brushed erect. Several commercial machines are availablewhich can provide this treatment, all of which are very expensive andhave various limitations.

One example of such a machine is the tensionless dryer. In this machinethe pile fabric is overfed onto a mesh belt which is then transportedthrough a long heated tunnel where either mechanical action orperpendicular air blasts directed through the belt cause the fabric toundergo rather gentle undulations; charging of the fabric occurs byfriction with the air or contact with various parts of the dryer. Therequired residence time results in a unit which may be several hundredfeet long and also in low fabric line speeds. There are quality problemsassociated with lack of edge control in such a long distance and also inmarks which may occur when the pile strikes the upper sections of thetunnel.

Another example of a pile conditioning device is the use of a highvelocity air jet unit such as disclosed in U.S. Pat. No. 4,837,902. Inthis case the fabric is heated to the desired temperature and theconditioning is accomplished almost instantaneously by vigorous sawtoothshaped waves that, although small in amplitude, are extremely effectivedue to the high accelerations normal to the fabric surface produced bythe combination of small bending radius and high wave velocity. Thedisadvantage to the process is direct contact of the heated fabric withthe air stream, which tensions the fabric and can set in distortions insensitive knit fabrics. Also, this process is less effective with highlypermeable fabrics, as the air may not be adequately trapped betweenfabric and plate.

It is therefore an object of the invention to provide an efficientapparatus and method to remove the pile distortions in a pile fabricafter it has been processed.

Other objects and advantages of the invention will become readilyapparent as the specification proceeds to describe the invention withreference to the accompanying drawings, in which:

FIG. 1 is a schematic side elevation view of the pile removal apparatusper se;

FIG. 2 is an isometric view of the pile removal apparatus per se;

FIG. 3 is a top view of the apparatus shown in FIG. 2 with parts removedto show the interior thereof;

FIG. 4 is a side view of FIG. 3 taken on line 4--4; and

FIGS. 5 and 6 are side and top views, respectively, of a portion of theapparatus shown in FIG. 2 to illustrate the principles of the invention.

Looking now to FIG. 1, the basic system is shown wherein a synthetic orpartially synthetic, woven, tufted or knit pile fabric 10, is beingsupplied to the treatment apparatus 12. The pile fabric 10 is deliveredover idler rolls 14 and 16 into the treatment chamber 18 after the pilesurface thereof has been brushed by the brush 20 to remove anyaccumulated deposit on the surface thereof. From the rolls 16 the fabric10 passes through the heating section between the radiant heaters 21 andthe steam heated plate 22 to the idler roll 24. If desired, the fabric10 can be charged either prior to or while being treated in the pileerector 26. This may be accomplished by using ionizing bars to spraycharge onto the fabric to be treated or by frictional contact of thefabric with the vibrating diaphragm which, in the latter case, shouldhave a surface resistance less than 100,000 ohms/square for adequatecharging. From the roll 24 the fabric 10 passes through the pile erector26 to the driven roll 28. From the roll 28 the treated fabric isdelivered successively through the conventional accumulator 30, over theroll 32 through the cooling zone 33, under the rolls 34 and 36 to theroll 38 where it is guided out of the treatment apparatus 12.

The radiant heater 21 facing the pile surface of the fabric 10 and thesteam heated plate 22 facing the back side of the fabric, collectively,raise the temperature of the fabric to a temperature between the heatsetting temperature and the dyeing temperature of the fabric 10. Thistemperature will vary according to the particular fabric beingprocessed. To maintain this selected temperature during processinganother steam heated plate 40 is mounted, facing the pile side of thefabric 10, by suitable members 42 to the pile erector 26.

The pile erector 26 is pivotally mounted through journal 44 connected tothe sides 45 of the pile erection 26 and telescoping the hollow shaft 54which is mounted to the sides of the apparatus 12. An arm 46 isconnected to the journal 44 at one end and engages the screw member 48at the other end. An air motor 50 is located at the upper end of thescrew member 48 to rotate same to cause the nut 52 to move up or downthe screw, depending on the direction of rotation, to pivot the free endof the pile erector 26 either upward or downward. The desired pivotalmovement of the pile erector 26 encompasses approximately 90°. Thispivotal movement allows ready access to the chamber 18 and the pileerector 26 by the operator for purposes of inspection, repair, cleaning,etc.

As discussed briefly before the pile erector 26 is supported in thechamber 18 by the hollow shaft 54 which extends across between the wallsof the apparatus 12. Connected to one end of the shaft 54 outside of thesides of the apparatus 12 is a fan or blower 55 supplying hot or coldair into the hollow shaft 54. From the hollow shaft 54, the supplied airis delivered into the interior of both of the support members 45 throughopenings (not shown). Mounted across the pile erector 26 on top of themembers 45 are a plurality of air manifolds 56 having openings therein(not shown) which cooperate with the openings 58 in the top of member 45to receive air from the interior of the member 45. The manifolds 56 aresecured in position by screws 57 projecting through the angle ironmembers 59 welded or otherwise secured to the inside wall of the member45. As shown in detail in FIG. 5 each of the manifolds 56 is notched atthe back and has an elongated strip 60 extending across the widththereof. The strip 60 has a plurality of notches 62 therein to cooperatewith matching holes 64 in the air manifold 56 to allow air to beprojected outwardly from the jet 66 formed by the bottom of the top ofthe notch 62 and the top surface 68 of the air manifold 56. If desiredfor maximum efficiency the jet 66 can be manufactured to provide aconverging-diverging shape.

For reasons hereinafter explained an impermeable, conductive, flexible,heat and fatigue resistant diaphragm 70 of silicone rubber, Tefloncoated fiberglass or other like material is secured above the airmanifolds 56 and below the path of travel of the fabric 10 to suitablebars 72. In use, as hereinafter explained, the upper surface of thediaphragm 70 is contacted by the fabric 10 as it travels through thepile erector 26 and, if not charged, should be charged while in contactwith the diaphragm 70.

To prevent excessive wear on the upper surface of the diaphragm 70 themechanism shown in FIGS. 3 and 4 is used to move the diaphragmlongitudinally and transversely to vary the areas of contact of thediaphragm by the air from jets 66. The diaphragm 70 is secured to bars72 by elongated cap members 74 securing the fabric 70 therebetween.Mounted between and secured to the members 45 at both ends thereof arehollow bars 76. Supported under each end of the hollow bars 76 andspaced therefrom by blocks 78 and 80 is a plate member 82 which providesa space 81 between the plate member 82 and the underside of the bar 76.Slidably supported in the space 81 is a bar 84 which has an upturnedmember 86 which supports the bar 72 to which it cooperates. Additionalbars 88 are connected to bar 84 to support the center bar 72. Anadditional cross bar 90 is connected between the bars 84 to cause themto act in tandem.

Screwed or otherwise secured to the hollow bars 76 are support plates 92and 94. Plate 92 rotably supports the drive motor 96 for the pulley 98driving the timing belt or chain 100 which drives the pulley 102 rotablymounted in on the plate 94. Also connected to the hollow bar 76 that theplate 94 is connected to are four support plates 104, 106, 108 and 110.Rotably mounted in each of said plates is a cam member 112 with a pin114 projecting downwardly therefrom. Above the cam member 112 fixed tothe shaft for the cam member is a pulley 116. All of the pulleys aredriven by the timing belt or chain 118 driven by the pulley 102. Mountedbetween the bars 84 is another bar 119 which has slots 120 and 122therein. Each of the bars 84 also have slots 124 and 126 therein. Eachof the pins 114 project downwardly into the slot adjacent the pulley 116to which its cam member 112 cooperates.

It can be seen that the continuously driven motor 96 through the drivingbelts 100 and 118 will cause the pins 114 in the slots 120 and 122 tocause the bar 119 to slide in the space 81 parallel to the path oftravel or the warp direction of the fabric 10 and the pins 114 in theslots 124 and 126 will cause the bar 119 to slide in the space which isparallel to the weft direction of the fabric. Since the bar 119 isconnected to the bars 84 to which the fabric support bars 72 areconnected, the diaphragm 70 will have a continuous motion which is acomposite of parallel and perpendicular motion of the bar 119 tocontinuously move the surface of the diaphragm 70 to spread the wearthereon by air from the jets 66. This continuous movement provides alonger service life for the diaphragm 70.

Looking at FIGS. 5 and 6 the action of the high velocity air from thejets 66 on the flexible diaphragm or fabric 70 and the pile fabric 10being processed is schematically represented. Since the jets 66 are notcontinuous across the pile erector 26 and are staggered in relation tothe jets 66 in the next adjacent row the air flow therefrom creates aseries of waves 130 the peaks of which in FIG. 6 are represented bycurvilinear lines. Because of the complex waveform created by thestaggered jets, the heated pile fabric 10 follows the contour of thediaphragm 70 created by the series of jets 66, as shown in FIG. 5. Acontinuous jet would produce more or less continuous waves which wouldcause the fabric to be bounced from the vibrating diaphragm, resultingin intermittent contact and reduced treatment. It should be noted thatthe curvilinear lines 130 adjacent the jets 66 are sharper and thendampen out as the air flow from the jets 66 diverges until the areaadjacent the next adjacent series of jets is substantially flat. Thecontinuous repeated action of the air from the series of jets 66 causesthe pile fibers of the fabric 10 to assume the erect position. Anexample of a fabric which has been successfully treated by theherein-disclosed apparatus is a double needle bar 44 gauge knitpolyester velvet having 70 denier, 54 filament polyester face yarns and70 denier, 34 filament polyester ground yarns. The fabric was knit insandwich form and heat set at a temperature in the range of 380°-415° F.The fabric was then slit to form two fabrics which were then dyed in apressurized jet dyeing machine at a temperature in the range of260°-287° F. The fabric was then backcoated and delivered to the pileerection machine. The fabric was then delivered to the pile erector at atemperature in the range of 300°-340° F. to the air jets which wereoperating in the range of 1.5-4.0 p.s.i.g., preferably 3.0 p.s.i.g.,whereat the fibers were erected to provide a smooth velour-type surface.

The herein-disclosed apparatus provides a very compact and efficientmethod to treat the fibers of a pile fabric to enhance the appearancethereof. Prior to this invention tensionless dryers have been used in anattempt to accomplish the desired result but these dryers did notprovide the desired effect and required large floor areas because oftheir bulkiness. The discontinuous slot arrangement along with the useof the intermediate diaphragm provides a system which is more easilycontrolled and results in a much more uniform product.

Although the preferred embodiment of the invention has been described,it is contemplated that changes may be made without departure from thescope or spirit of the invention and it is desired that the invention belimited only by the scope of the claims.

I claim:
 1. Method to erect the fibers of a synthetic pile fabriccomprising the steps of: supplying a web of pile fabric, heating thepile fabric to a temperature between the heat setting and dyeingtemperature of the fabric, supplying the pile fabric over and in contactwith a diaphragm, supplying a plurality of separate air streams againstthe underside of the diaphragm to create a plurality of waves therein tocreate waves in the pile fabric to cause the fibers therein to becomeerect and supplying the pile fabric with erect fibers to a point oftake-up.
 2. The method of claim 1 wherein the air streams are suppliedat high velocity against the diaphragm.
 3. The method of claim 2 whereinthe air streams are supplied at a low pressure.
 4. The method of claim 3wherein the pressure of the air supplied is in the range of 1.5-4.0p.s.i.g.
 5. The method of claim 3 wherein the pressure of the airsupplied is approximately 3.0 p.s.i.g.
 6. The method of claim 1 whereinthe diaphragm is continuously moved with respect to the supplied fabricto increase the service life of the diaphragm.
 7. The method of claim 1wherein the air streams are supplied from a plurality of jets locatedacross the underside of the diaphragm and a plurality of rows of airjets spaced downstream from one another.
 8. The method of claim 7wherein the air streams from one row are staggered in relation to theair streams in the next adjacent row.
 9. The method of claim 8 whereinthe diaphragm is continuously moved with respect to the jets to increasethe service life of the diaphragm.
 10. The method of claim 9 wherein thepressure of the air supplied is in the range of 1.5-4.0 p.s.i.g.
 11. Themethod of claim 1 wherein the pile fabric is charged.
 12. The method ofclaim 11 wherein the pile fabric is charged prior to contact with thediaphragm.
 13. The method of claim 11 wherein the pile fabric is chargedwhile in contact with the diaphragm.
 14. The methods of claim 11, 12 or13 wherein the surface resistance of the diaphragm is less than 100,000ohms/square.
 15. The method of claim 1 wherein the pile fabric isbrushed prior to being heated.
 16. Apparatus to erect the pile fibers ofa synthetic pile fabric comprising: a frame, a first heater meansmounted in said frame, a pile erector mounted in said frame, a firstmeans to supply fabric into operative relationship with said heatermeans and then onto said pile erector and a second means to directfabric from said frame after passage over said pile erector, said pileerector including a plurality of rows of air ejectors, each of said rowsbeing a plurality of air ejectors, a diaphragm connected to the top ofsaid erector over said rows of air ejectors and under the path of travelof the pile fabric, said air ejectors blowing high velocity air againstthe underside of said diaphragm to create waves therein.
 17. Theapparatus of claim 16 wherein the air ejectors in one row are staggeredin relationship to the air ejectors in the next adjacent rows.
 18. Theapparatus of claim 17 wherein said pile erector includes a means tooscillate said diaphragm to reduce the wear thereof.
 19. The apparatusof claim 17 wherein the air supplied to said air ejectors is within arange of pressure of 1.5 to 4.0 p.s.i.g.
 20. The apparatus of claim 18wherein the air supplied to said air ejectors is at a pressure of about3.0 p.s.i.g.
 21. The apparatus of claim 16 wherein a second heater meansis mounted above the path of travel of the pile fabric over the pileerector.
 22. Apparatus to treat the pile fibers of a pile fabriccomprising: a frame, said frame having two hollow support members spacedfrom one another, a hollow shaft member mounted through said supportmembers and being in communication with the interior of each of members,air supply means operably associated with said shaft member, a pluralityof air manifolds mounted across said support members and spaced from oneanother, means supplying communication between said support members andsaid air manifolds, each of said manifolds having a plurality of airjets and a diaphragm movably mounted above said air jets.
 23. Theapparatus of claim 22 wherein the air jets in one manifold are staggeredin relation to the air jets in the next adjacent manifold.
 24. Theapparatus of claim 23 wherein said pile erector includes a means tooscillate said diaphragm.
 25. The apparatus of claim 24 wherein a heatermeans is mounted to said frame above said diaphragm.